Thermostatic switch



March 12, 1929. a BLOCH ET AL 1,705,391

THERMOSTATIC SWITQH Filed Feb. 13, 1926 2 Sheets-Sheet 1 IIIIIHIIHHHIIHIHHH i i... mmm

2/ f iw March 12, 1929. P. BLOCH ET AL 1,705,391

THERMOSTATIC SWITCH Filed Feb. 13, 1926 2 Sheets-Sheet 2 Even/ford Zrre 31ml in] flfznczszz z Wufigg- Patented M 12, 1929.

2mm BLOCK mi ATANASIO NUfi'Ez, or MEXICO CITY; MEXICO.

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Application filed. February 13, 1926, Serial No. 88,108. and in Mexico August 20, 1925.

- Thisinvention relates to a method for interrupting an electric current due to the expansion of some fluid which displaces a body' of mercury, as the result of thermic transformation in a conductor extended within the fluid. V

The object of the invention is to provide 1 ;a method and apparatus by which the increased temperature of a conducting wire,

resulting from excess passage of current, shall expand hydrogen or helium contained in a vessel, into which extends one end of the conducting wire.

The vessel or bulb is communicated with a displacer tube containing, mercury, so that onept-two wires, both normally immersed into the opposite extremes of the mercury, remains out of the mercury when the hydrogen expands, thus rejecting the mercury into the displacer tube.

Another object is to rovide the bulb with a foot-tube mercury eposit for adjusting the quantity of mercury contained in the displacer-tube, so as to afford interruptlon at different temperatures determined by the current passing through the bulb wire.

Another object is to combine a lock coil with the interrupter, which shall positively interrupt the current, when by effect of the interrupting in the interrupter the current is deviated to the lock coi1,'and before the mercury may re-establish the current through the interrupter bulb.

Fig. 1 is a side elevation of-the interrupter in interrupted position.

Fig. 2 1s a top view of same. 7 Fig. 3 is a perspective view of the mterrupter. 1

F ig. 4 is a front view'of an automatic switch and interrupter.

Fig. .5 is a plan of the cover for same. The a aratu's is interposed on the main line 1 w ich is attached to the. contact plate (2) by the screw (3). The plate 2 has a central projection 4 formin partpf the stationary bridge 5 through w ich rises a spindle 6. A swing bridge 7 having an isolated center and tubular'shaft 8 is mounted on thlS. spindle 6, and a spring 6 within the tube 8, attached to the spindle 6 as well as to the tube 8, elasticallyholds the swing bridge 7 aligned with the stationary bridge5, when no current passes through the coil 3031. This swing bridge 7, shown in Figs. 1 and 2 as turned to ,ofi' position, is due to the spring 6 set so as to rest lengthwise on top of the stationary bridge 5, by which current shall be divided and passed to the curved rails 9 and 10, therefrom to their contact screwsll and 12. By the line 13 current is sent to the distribution within the building and by the line 14 current is given to the passes through the mercury, which shallv have fallen down in the displacer tube, so as to make contact with the spiral wire (22) in the bulb (23) containing dry hydrogen or helium at apressure less than atmospheric.

Here it should be explained that normally, when no excess current passes through the interrupter, the mercury does not. stand raised in the,displacer tube as shown in Fig. 1, which shows the mercury raised as the result of increased pressure following the heating of the hydrogen, by excess charge of the spiral wire (22).

From this spiral wire 22 the current goes to the knife switch 24 and out to the same main line at 25 where this was cut in order to interpose the interrupter.

Now we shall see what happens when excess current passes through the spiral wire 22in the bulb 23. I

p The hydrogen being heated by the wire expands and the augmented pressure therefor rejects the mercury into the displacer tube 20 and by thus raisin the mercury will contact with the inserte end 26 of the wire 27.

Instead of passing through the spiral wire 22 which'is no longer in contact with the mercury, the current goes by the wire 27 to the contact 0st 28, through the curved rail 29, from tli re it passes by a roller on the end of coil leg30, therefrom over to the other coil leg 31, through its roller down to the curved rail 32, to the contact post 33 and by the wire 34 out through the knife switch pivot to the main line at 25.

The coilis provided on its top with a pivot 35 for .maintaining the coil upright though swingable, and from the coil extends a small bar 36 which, when the coil by attraction to the stationary coil 16 slides over a rail 37 fastened at 38" to the back 39 of the box, falls into the groove i0 so as to lock the interrupter which otherwise when the hydrogen cools ofi would re-establish the circuit. On the lower end of the bulb 23 is a deposit tube 41 into which some mercury may be'poured from the displacer tube 20, when the bulb is swung over the pivot'42 fastened to the back 39 of the box, which pivot supports the brace 43 around the bulb.

By so pouring mercury from either the tube '20 or the tube 41, adjustment is obtained of the powerallowed.

In Fig. 4 is shown an interrupter which, as soon as the pressure falls in the bulb 44, re-establishes the current. Here the current enters at 45 connected to the plate 46, following through the wire 47 which enters at 48 into the displacer tube 49., then through the mercury to the spiral wire 50 and out through a lamp not shown, therefrom back by the wire 51 to the main line 52. The bulb is supported by a brace 53 turning on the pivot or screw 54 fastened to the box 55. Fig. 5 shows thec'over 56 for the box. In this construction like in the previously described,v the bulb may be swun so as to pour mercury from or .to

the d isplacer tube 49 or the deposit tube 56, so as to adjust the power allowed to pass without interrupting the current.

We claim:

1. A thermo-electric interrupter including a gas filled bulb provided with a depending mercury deposit foot tube, a displacer tube communicating at its lower end with the bottom of said bulb, a heating 7 wire extending through the bulb and into the lower end of the displacer tube, and a further wire extending into the upper end portion of the displacer tube.

2. A thermo-electric interrupter including a gas filled bulb provided with a depending mercury deposit foot tube, a displacer tube communicating at its lower end with the bottom of said bulb, a heating wire extending through the bulb and into the lower end of the displacer tube, a further wire extending into the upper end portion of the displacer tube, and means to mount the-bulb and tube for tilting movement to effect transfer of mercury from the foot \tube to the displacer tube or vice versa, at

will. I e

3. A thermo-electric interrupter as set forth in claim 2, wherein the heating wire and said further wire normally enter the mercury in the displacer tube, and wherein a still further wire extends into the upper end POItlOIl'O'f the displacer tube above the normal level of the mercury in the latter.

In testimony whereof we afiix' our signatures.

PIERRE BLOCH. ATANASIO UNEZ. 

